Analytical Multi-Physics modelling of (gapped) inductors
The design of power electronic systems is typically performed with optimisation procedures, where analytical models of the system and its components are used. One important component of power electronic converter systems is the switching cell. A switching cell design consists of the semiconductor devices, the gate drivers, the DC-link capacitors, and the heat sink. The arrangement of these components has significant impact on the electrical and thermal performance of the converter.
At HPE, analytical calculation models for inductors with air gaps are developed for accurately describing the winding losses. The focus of this project is twofold: First, on the highly accurate calculation of the impact of the air gap field on the component's properties, and second, on the required calculation time of the models. Hereby, calculation times in the millisecond range are targeted, with an accuracy tolerance of less than 25% error.
The developed models are based on fully analytical derivations using the Maxwell equations. These accurately describe the field distribution within the component. With the determined magnetic field, both the frequency-dependent inductance and the frequency-dependent winding losses are calculated. The winding losses, in combination with the core losses, determine the temperature increase of the component, which is also calculated based on analytical calculation models. All models are validated with prototypes.